import cv2
import numpy as np


# mouse callback function
def draw_circle(event, x, y, flags, param):
    if event==cv2.EVENT_LBUTTONDBLCLK:
        cv2.circle(img,(x,y),100,(255,0,0),-1) # 创建图像与窗口并将窗口与回调函数绑定


img=np.zeros((1024,1024,3),np.uint8)
cv2.namedWindow('image')
cv2.setMouseCallback('image',draw_circle)

while 1:
    cv2.imshow('image',img)
    if cv2.waitKey(20)&0xFF==27:
        break
cv2.destroyAllWindows()